larry kane. >> pictures of damage after the tornado is all about impact. >> where wind really becomes an issue is the debris opens up the building envelope, the walls, the roof. once you have that envelope opened, now you've got double the trouble. the most predominant projectile that we see in these storms is normally something like a two by four. >> so what you tend to see coming out of this cannon is what you tend to see flying around when a tornado is centered? >> absolutely. we do tornado research for the national science foundation back in may after the moore tornado. specifically just to look for shelters in the storm path. >> the question now is: not whether to rebuild, but how. >> we're smart engineers. we know how to design for the wind speeds. and now, we know how to design for impact resistance. >> research performed tests on a variety of building materials. some of them failed. through trial and error, oinvocation came in the form of reinforcement and engineering. >> should we -- load the ca can? >> load the cannon. okay, let's do it. >> wow! >> 103 miles per hour. >> 103